1. Field of the Invention
The present invention relates to a cable cutter for cutting cables such as telecommunication wires, and especially to a cable cutter which is portable and which cuts cables by driving a planetary reduction gear with an electric motor.
2. Prior Art
Cable cutters are utilized for cutting telecommunication wires, electric wires and other cables during construction. One kind of the conventional cable cutters holds an electric wire between clamps and cuts it with a hydraulic cutter. Another kind of cable cutters is a hand-operated cutter shown in FIG. 1. This cutter comprises a link 101 having a blade 101a at one end, a link 102 having a blade 102a, a link 103, and handles 104, 105, which constitute a toggle mechanism. In this cutter, as the handle 104 and the handle 109 are rotated in directions shown by arrows in FIG. 1, the blade 101a and the blade 102a are rotated around a shaft 106 in different directions, and a cable or the like held between the blades 101a, 102a is cut by a shearing stress.
Another kind of cutters is an electric cable cutter. The electric cable cutter comprises a cord to be connected to a power source, a driving unit for driving a blade, and a switch for starting and stopping the driving unit. A switch lever for operating the switch is provided on a handle where fingers are put on easily. In general, most of the switch levers have a safety unit (safety switch lever) not to operate the driving unit when the finger or the other part of the body accidentally touches the switch.
Most of the safety switch levers have the structure that the movement of the switch lever is prevented even though the switch lever is pressed. For example, a link moved together with a button is placed near the switch lever, and as the button is moved with the finger, the link prevents the movement of the switch lever.
Workers at the construction have to work under restricted circumstances, i.e., supporting their bodies by one hand at height, holding much stuff. Accordingly, the worker needs to utilize some kinds of supplementary units to use the cable cutter at inconvenient places such as at height and also needs physical strength.
Further, in the electric cutters having the safety switch lever, the safety switch lever cannot be operated by one hand, particularly by the hand (fingers) holding the cutter. Furthermore, since the cord to be connected to the power source is required, this kind of cutters can be used at the limited places.